A background noise may interfere with a clarity of a speech signal. The background noise may vary over time or due to environmental conditions. A filter may reduce the background noise, but the filter may not correlate with the background noise. As a result, the filter may fail to reduce a part of the background noise. The filter may also reduce an additional part of the speech signal below a threshold tolerance. The speech signal may therefore become distorted or reduced, and a part of the noise signal may continue to interfere with the clarity of the speech signal.